1. Field of Invention
The present invention relates generally to electrical chargers for electronic devices. More specifically, the present invention relates to vehicle electrical chargers for electronic devices with universal serial buses (USB).
2. Description of Related Art
Since Apple Inc. has sold hundreds of millions of portable personal electronic devices such as iPods®, iPhones® and iPads®, a means to recharge their internal batteries while being used in the car is necessary. This is normally accomplished with a device that plugs into the vehicle's cigarette lighter socket that converts the vehicles loosely regulated voltage of 13.8 volts to the USB standard of 4.75 to 5.25 volts.
Various cabling arrangements are being used from a standard USB cable to different length coil cords. The electronic circuits are typically step-down switching regulators. Most manufacturers of these adapters want to have them certified by Apple Inc. as “Works With iPhone®” and/or “Made for iPod®”. To get this certification, the adapter must meet all the requirements of the Apple Inc. specification. When marketing a product in such a competitive environment, price is of prime concern.